xref: /freebsd/lib/libc/locale/collate.c (revision ebacd8013fe5f7fdf9f6a5b286f6680dd2891036)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright 2014 Garrett D'Amore <garrett@damore.org>
5  * Copyright 2010 Nexenta Systems, Inc.  All rights reserved.
6  * Copyright (c) 1995 Alex Tatmanjants <alex@elvisti.kiev.ua>
7  *		at Electronni Visti IA, Kiev, Ukraine.
8  *			All rights reserved.
9  *
10  * Copyright (c) 2011 The FreeBSD Foundation
11  *
12  * Portions of this software were developed by David Chisnall
13  * under sponsorship from the FreeBSD Foundation.
14  *
15  * Redistribution and use in source and binary forms, with or without
16  * modification, are permitted provided that the following conditions
17  * are met:
18  * 1. Redistributions of source code must retain the above copyright
19  *    notice, this list of conditions and the following disclaimer.
20  * 2. Redistributions in binary form must reproduce the above copyright
21  *    notice, this list of conditions and the following disclaimer in the
22  *    documentation and/or other materials provided with the distribution.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND
25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE
28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34  * SUCH DAMAGE.
35  *
36  * Adapted to xlocale by John Marino <draco@marino.st>
37  */
38 
39 #include <sys/cdefs.h>
40 __FBSDID("$FreeBSD$");
41 
42 #include "namespace.h"
43 
44 #include <sys/types.h>
45 #include <sys/stat.h>
46 #include <sys/mman.h>
47 
48 #include <assert.h>
49 #include <stdio.h>
50 #include <stdlib.h>
51 #include <string.h>
52 #include <wchar.h>
53 #include <errno.h>
54 #include <unistd.h>
55 #include <fcntl.h>
56 #include "un-namespace.h"
57 
58 #include "collate.h"
59 #include "setlocale.h"
60 #include "ldpart.h"
61 #include "libc_private.h"
62 
63 struct xlocale_collate __xlocale_global_collate = {
64 	{{0}, "C"}, 1, 0, 0, 0
65 };
66 
67 struct xlocale_collate __xlocale_C_collate = {
68 	{{0}, "C"}, 1, 0, 0, 0
69 };
70 
71 struct xlocale_collate __xlocale_POSIX_collate = {
72 	{{0}, "POSIX"}, 1, 0, 0, 0
73 };
74 
75 struct xlocale_collate __xlocale_CUTF8_collate = {
76 	{{0}, "C.UTF-8"}, 1, 0, 0, 0
77 };
78 
79 static int
80 __collate_load_tables_l(const char *encoding, struct xlocale_collate *table);
81 
82 static void
83 destruct_collate(void *t)
84 {
85 	struct xlocale_collate *table = t;
86 	if (table->map && (table->maplen > 0)) {
87 		(void) munmap(table->map, table->maplen);
88 	}
89 	free(t);
90 }
91 
92 void *
93 __collate_load(const char *encoding, __unused locale_t unused)
94 {
95 	if (strcmp(encoding, "C") == 0)
96 		return (&__xlocale_C_collate);
97 	else if (strcmp(encoding, "POSIX") == 0)
98 		return (&__xlocale_POSIX_collate);
99 	else if (strcmp(encoding, "C.UTF-8") == 0)
100 		return (&__xlocale_CUTF8_collate);
101 
102 	struct xlocale_collate *table = calloc(sizeof(struct xlocale_collate),
103 	    1);
104 	if (table == NULL)
105 		return (NULL);
106 	table->header.header.destructor = destruct_collate;
107 
108 	/*
109 	 * FIXME: Make sure that _LDP_CACHE is never returned.  We
110 	 * should be doing the caching outside of this section.
111 	 */
112 	if (__collate_load_tables_l(encoding, table) != _LDP_LOADED) {
113 		xlocale_release(table);
114 		return (NULL);
115 	}
116 	return (table);
117 }
118 
119 /**
120  * Load the collation tables for the specified encoding into the global table.
121  */
122 int
123 __collate_load_tables(const char *encoding)
124 {
125 
126 	return (__collate_load_tables_l(encoding, &__xlocale_global_collate));
127 }
128 
129 static int
130 __collate_load_tables_l(const char *encoding, struct xlocale_collate *table)
131 {
132 	int i, chains, z;
133 	char *buf;
134 	char *TMP;
135 	char *map;
136 	collate_info_t *info;
137 	struct stat sbuf;
138 	int fd;
139 
140 	table->__collate_load_error = 1;
141 
142 	/* 'encoding' must be already checked. */
143 	if (strcmp(encoding, "C") == 0 || strcmp(encoding, "POSIX") == 0 ||
144 	    strncmp(encoding, "C.", 2) == 0) {
145 		return (_LDP_CACHE);
146 	}
147 
148 	if (asprintf(&buf, "%s/%s/LC_COLLATE", _PathLocale, encoding) == -1)
149 		return (_LDP_ERROR);
150 
151 	if ((fd = _open(buf, O_RDONLY | O_CLOEXEC)) < 0) {
152 		free(buf);
153 		return (_LDP_ERROR);
154 	}
155 	free(buf);
156 	if (_fstat(fd, &sbuf) < 0) {
157 		(void) _close(fd);
158 		return (_LDP_ERROR);
159 	}
160 	if (sbuf.st_size < (COLLATE_FMT_VERSION_LEN +
161 			    XLOCALE_DEF_VERSION_LEN +
162 			    sizeof (info))) {
163 		(void) _close(fd);
164 		errno = EINVAL;
165 		return (_LDP_ERROR);
166 	}
167 	map = mmap(NULL, sbuf.st_size, PROT_READ, MAP_PRIVATE, fd, 0);
168 	(void) _close(fd);
169 	if ((TMP = map) == MAP_FAILED) {
170 		return (_LDP_ERROR);
171 	}
172 
173 	if (strncmp(TMP, COLLATE_FMT_VERSION, COLLATE_FMT_VERSION_LEN) != 0) {
174 		(void) munmap(map, sbuf.st_size);
175 		errno = EINVAL;
176 		return (_LDP_ERROR);
177 	}
178 	TMP += COLLATE_FMT_VERSION_LEN;
179 	strlcat(table->header.version, TMP, sizeof (table->header.version));
180 	TMP += XLOCALE_DEF_VERSION_LEN;
181 
182 	info = (void *)TMP;
183 	TMP += sizeof (*info);
184 
185 	if ((info->directive_count < 1) ||
186 	    (info->directive_count >= COLL_WEIGHTS_MAX) ||
187 	    ((chains = info->chain_count) < 0)) {
188 		(void) munmap(map, sbuf.st_size);
189 		errno = EINVAL;
190 		return (_LDP_ERROR);
191 	}
192 
193 	i = (sizeof (collate_char_t) * (UCHAR_MAX + 1)) +
194 	    (sizeof (collate_chain_t) * chains) +
195 	    (sizeof (collate_large_t) * info->large_count);
196 	for (z = 0; z < info->directive_count; z++) {
197 		i += sizeof (collate_subst_t) * info->subst_count[z];
198 	}
199 	if (i != (sbuf.st_size - (TMP - map))) {
200 		(void) munmap(map, sbuf.st_size);
201 		errno = EINVAL;
202 		return (_LDP_ERROR);
203 	}
204 
205 	if (table->map && (table->maplen > 0)) {
206 		(void) munmap(table->map, table->maplen);
207 	}
208 	table->map = map;
209 	table->maplen = sbuf.st_size;
210 	table->info = info;
211 	table->char_pri_table = (void *)TMP;
212 	TMP += sizeof (collate_char_t) * (UCHAR_MAX + 1);
213 
214 	for (z = 0; z < info->directive_count; z++) {
215 		if (info->subst_count[z] > 0) {
216 			table->subst_table[z] = (void *)TMP;
217 			TMP += info->subst_count[z] * sizeof (collate_subst_t);
218 		} else {
219 			table->subst_table[z] = NULL;
220 		}
221 	}
222 
223 	if (chains > 0) {
224 		table->chain_pri_table = (void *)TMP;
225 		TMP += chains * sizeof (collate_chain_t);
226 	} else
227 		table->chain_pri_table = NULL;
228 	if (info->large_count > 0)
229 		table->large_pri_table = (void *)TMP;
230 	else
231 		table->large_pri_table = NULL;
232 
233 	table->__collate_load_error = 0;
234 	return (_LDP_LOADED);
235 }
236 
237 static const int32_t *
238 substsearch(struct xlocale_collate *table, const wchar_t key, int pass)
239 {
240 	const collate_subst_t *p;
241 	int n = table->info->subst_count[pass];
242 
243 	if (n == 0)
244 		return (NULL);
245 
246 	if (pass >= table->info->directive_count)
247 		return (NULL);
248 
249 	if (!(key & COLLATE_SUBST_PRIORITY))
250 		return (NULL);
251 
252 	p = table->subst_table[pass] + (key & ~COLLATE_SUBST_PRIORITY);
253 	assert(p->key == key);
254 
255 	return (p->pri);
256 }
257 
258 static collate_chain_t *
259 chainsearch(struct xlocale_collate *table, const wchar_t *key, int *len)
260 {
261 	int low = 0;
262 	int high = table->info->chain_count - 1;
263 	int next, compar, l;
264 	collate_chain_t *p;
265 	collate_chain_t *tab = table->chain_pri_table;
266 
267 	if (high < 0)
268 		return (NULL);
269 
270 	while (low <= high) {
271 		next = (low + high) / 2;
272 		p = tab + next;
273 		compar = *key - *p->str;
274 		if (compar == 0) {
275 			l = wcsnlen(p->str, COLLATE_STR_LEN);
276 			compar = wcsncmp(key, p->str, l);
277 			if (compar == 0) {
278 				*len = l;
279 				return (p);
280 			}
281 		}
282 		if (compar > 0)
283 			low = next + 1;
284 		else
285 			high = next - 1;
286 	}
287 	return (NULL);
288 }
289 
290 static collate_large_t *
291 largesearch(struct xlocale_collate *table, const wchar_t key)
292 {
293 	int low = 0;
294 	int high = table->info->large_count - 1;
295 	int next, compar;
296 	collate_large_t *p;
297 	collate_large_t *tab = table->large_pri_table;
298 
299 	if (high < 0)
300 		return (NULL);
301 
302 	while (low <= high) {
303 		next = (low + high) / 2;
304 		p = tab + next;
305 		compar = key - p->val;
306 		if (compar == 0)
307 			return (p);
308 		if (compar > 0)
309 			low = next + 1;
310 		else
311 			high = next - 1;
312 	}
313 	return (NULL);
314 }
315 
316 void
317 _collate_lookup(struct xlocale_collate *table, const wchar_t *t, int *len,
318     int *pri, int which, const int **state)
319 {
320 	collate_chain_t *p2;
321 	collate_large_t *match;
322 	int p, l;
323 	const int *sptr;
324 
325 	/*
326 	 * If this is the "last" pass for the UNDEFINED, then
327 	 * we just return the priority itself.
328 	 */
329 	if (which >= table->info->directive_count) {
330 		*pri = *t;
331 		*len = 1;
332 		*state = NULL;
333 		return;
334 	}
335 
336 	/*
337 	 * If we have remaining substitution data from a previous
338 	 * call, consume it first.
339 	 */
340 	if ((sptr = *state) != NULL) {
341 		*pri = *sptr;
342 		sptr++;
343 		if ((sptr == *state) || (sptr == NULL))
344 			*state = NULL;
345 		else
346 			*state = sptr;
347 		*len = 0;
348 		return;
349 	}
350 
351 	/* No active substitutions */
352 	*len = 1;
353 
354 	/*
355 	 * Check for composites such as diphthongs that collate as a
356 	 * single element (aka chains or collating-elements).
357 	 */
358 	if (((p2 = chainsearch(table, t, &l)) != NULL) &&
359 	    ((p = p2->pri[which]) >= 0)) {
360 
361 		*len = l;
362 		*pri = p;
363 
364 	} else if (*t <= UCHAR_MAX) {
365 
366 		/*
367 		 * Character is a small (8-bit) character.
368 		 * We just look these up directly for speed.
369 		 */
370 		*pri = table->char_pri_table[*t].pri[which];
371 
372 	} else if ((table->info->large_count > 0) &&
373 	    ((match = largesearch(table, *t)) != NULL)) {
374 
375 		/*
376 		 * Character was found in the extended table.
377 		 */
378 		*pri = match->pri.pri[which];
379 
380 	} else {
381 		/*
382 		 * Character lacks a specific definition.
383 		 */
384 		if (table->info->directive[which] & DIRECTIVE_UNDEFINED) {
385 			/* Mask off sign bit to prevent ordering confusion. */
386 			*pri = (*t & COLLATE_MAX_PRIORITY);
387 		} else {
388 			*pri = table->info->undef_pri[which];
389 		}
390 		/* No substitutions for undefined characters! */
391 		return;
392 	}
393 
394 	/*
395 	 * Try substituting (expanding) the character.  We are
396 	 * currently doing this *after* the chain compression.  I
397 	 * think it should not matter, but this way might be slightly
398 	 * faster.
399 	 *
400 	 * We do this after the priority search, as this will help us
401 	 * to identify a single key value.  In order for this to work,
402 	 * its important that the priority assigned to a given element
403 	 * to be substituted be unique for that level.  The localedef
404 	 * code ensures this for us.
405 	 */
406 	if ((sptr = substsearch(table, *pri, which)) != NULL) {
407 		if ((*pri = *sptr) > 0) {
408 			sptr++;
409 			*state = *sptr ? sptr : NULL;
410 		}
411 	}
412 
413 }
414 
415 /*
416  * This is the meaty part of wcsxfrm & strxfrm.  Note that it does
417  * NOT NULL terminate.  That is left to the caller.
418  */
419 size_t
420 _collate_wxfrm(struct xlocale_collate *table, const wchar_t *src, wchar_t *xf,
421     size_t room)
422 {
423 	int		pri;
424 	int		len;
425 	const wchar_t	*t;
426 	wchar_t		*tr = NULL;
427 	int		direc;
428 	int		pass;
429 	const int32_t 	*state;
430 	size_t		want = 0;
431 	size_t		need = 0;
432 	int		ndir = table->info->directive_count;
433 
434 	assert(src);
435 
436 	for (pass = 0; pass <= ndir; pass++) {
437 
438 		state = NULL;
439 
440 		if (pass != 0) {
441 			/* insert level separator from the previous pass */
442 			if (room) {
443 				*xf++ = 1;
444 				room--;
445 			}
446 			want++;
447 		}
448 
449 		/* special pass for undefined */
450 		if (pass == ndir) {
451 			direc = DIRECTIVE_FORWARD | DIRECTIVE_UNDEFINED;
452 		} else {
453 			direc = table->info->directive[pass];
454 		}
455 
456 		t = src;
457 
458 		if (direc & DIRECTIVE_BACKWARD) {
459 			wchar_t *bp, *fp, c;
460 			free(tr);
461 			if ((tr = wcsdup(t)) == NULL) {
462 				errno = ENOMEM;
463 				goto fail;
464 			}
465 			bp = tr;
466 			fp = tr + wcslen(tr) - 1;
467 			while (bp < fp) {
468 				c = *bp;
469 				*bp++ = *fp;
470 				*fp-- = c;
471 			}
472 			t = (const wchar_t *)tr;
473 		}
474 
475 		if (direc & DIRECTIVE_POSITION) {
476 			while (*t || state) {
477 				_collate_lookup(table, t, &len, &pri, pass, &state);
478 				t += len;
479 				if (pri <= 0) {
480 					if (pri < 0) {
481 						errno = EINVAL;
482 						goto fail;
483 					}
484 					state = NULL;
485 					pri = COLLATE_MAX_PRIORITY;
486 				}
487 				if (room) {
488 					*xf++ = pri;
489 					room--;
490 				}
491 				want++;
492 				need = want;
493 			}
494 		} else {
495 			while (*t || state) {
496 				_collate_lookup(table, t, &len, &pri, pass, &state);
497 				t += len;
498 				if (pri <= 0) {
499 					if (pri < 0) {
500 						errno = EINVAL;
501 						goto fail;
502 					}
503 					state = NULL;
504 					continue;
505 				}
506 				if (room) {
507 					*xf++ = pri;
508 					room--;
509 				}
510 				want++;
511 				need = want;
512 			}
513 		}
514 	}
515 	free(tr);
516 	return (need);
517 
518 fail:
519 	free(tr);
520 	return ((size_t)(-1));
521 }
522 
523 /*
524  * In the non-POSIX case, we transform each character into a string of
525  * characters representing the character's priority.  Since char is usually
526  * signed, we are limited by 7 bits per byte.  To avoid zero, we need to add
527  * XFRM_OFFSET, so we can't use a full 7 bits.  For simplicity, we choose 6
528  * bits per byte.
529  *
530  * It turns out that we sometimes have real priorities that are
531  * 31-bits wide.  (But: be careful using priorities where the high
532  * order bit is set -- i.e. the priority is negative.  The sort order
533  * may be surprising!)
534  *
535  * TODO: This would be a good area to optimize somewhat.  It turns out
536  * that real prioririties *except for the last UNDEFINED pass* are generally
537  * very small.  We need the localedef code to precalculate the max
538  * priority for us, and ideally also give us a mask, and then we could
539  * severely limit what we expand to.
540  */
541 #define	XFRM_BYTES	6
542 #define	XFRM_OFFSET	('0')	/* make all printable characters */
543 #define	XFRM_SHIFT	6
544 #define	XFRM_MASK	((1 << XFRM_SHIFT) - 1)
545 #define	XFRM_SEP	('.')	/* chosen to be less than XFRM_OFFSET */
546 
547 static int
548 xfrm(struct xlocale_collate *table, unsigned char *p, int pri, int pass)
549 {
550 	/* we use unsigned to ensure zero fill on right shift */
551 	uint32_t val = (uint32_t)table->info->pri_count[pass];
552 	int nc = 0;
553 
554 	while (val) {
555 		*p = (pri & XFRM_MASK) + XFRM_OFFSET;
556 		pri >>= XFRM_SHIFT;
557 		val >>= XFRM_SHIFT;
558 		p++;
559 		nc++;
560 	}
561 	return (nc);
562 }
563 
564 size_t
565 _collate_sxfrm(struct xlocale_collate *table, const wchar_t *src, char *xf,
566     size_t room)
567 {
568 	int		pri;
569 	int		len;
570 	const wchar_t	*t;
571 	wchar_t		*tr = NULL;
572 	int		direc;
573 	int		pass;
574 	const int32_t 	*state;
575 	size_t		want = 0;
576 	size_t		need = 0;
577 	int		b;
578 	uint8_t		buf[XFRM_BYTES];
579 	int		ndir = table->info->directive_count;
580 
581 	assert(src);
582 
583 	for (pass = 0; pass <= ndir; pass++) {
584 
585 		state = NULL;
586 
587 		if (pass != 0) {
588 			/* insert level separator from the previous pass */
589 			if (room) {
590 				*xf++ = XFRM_SEP;
591 				room--;
592 			}
593 			want++;
594 		}
595 
596 		/* special pass for undefined */
597 		if (pass == ndir) {
598 			direc = DIRECTIVE_FORWARD | DIRECTIVE_UNDEFINED;
599 		} else {
600 			direc = table->info->directive[pass];
601 		}
602 
603 		t = src;
604 
605 		if (direc & DIRECTIVE_BACKWARD) {
606 			wchar_t *bp, *fp, c;
607 			free(tr);
608 			if ((tr = wcsdup(t)) == NULL) {
609 				errno = ENOMEM;
610 				goto fail;
611 			}
612 			bp = tr;
613 			fp = tr + wcslen(tr) - 1;
614 			while (bp < fp) {
615 				c = *bp;
616 				*bp++ = *fp;
617 				*fp-- = c;
618 			}
619 			t = (const wchar_t *)tr;
620 		}
621 
622 		if (direc & DIRECTIVE_POSITION) {
623 			while (*t || state) {
624 
625 				_collate_lookup(table, t, &len, &pri, pass, &state);
626 				t += len;
627 				if (pri <= 0) {
628 					if (pri < 0) {
629 						errno = EINVAL;
630 						goto fail;
631 					}
632 					state = NULL;
633 					pri = COLLATE_MAX_PRIORITY;
634 				}
635 
636 				b = xfrm(table, buf, pri, pass);
637 				want += b;
638 				if (room) {
639 					while (b) {
640 						b--;
641 						if (room) {
642 							*xf++ = buf[b];
643 							room--;
644 						}
645 					}
646 				}
647 				need = want;
648 			}
649 		} else {
650 			while (*t || state) {
651 				_collate_lookup(table, t, &len, &pri, pass, &state);
652 				t += len;
653 				if (pri <= 0) {
654 					if (pri < 0) {
655 						errno = EINVAL;
656 						goto fail;
657 					}
658 					state = NULL;
659 					continue;
660 				}
661 
662 				b = xfrm(table, buf, pri, pass);
663 				want += b;
664 				if (room) {
665 
666 					while (b) {
667 						b--;
668 						if (room) {
669 							*xf++ = buf[b];
670 							room--;
671 						}
672 					}
673 				}
674 				need = want;
675 			}
676 		}
677 	}
678 	free(tr);
679 	return (need);
680 
681 fail:
682 	free(tr);
683 	return ((size_t)(-1));
684 }
685 
686 /*
687  * __collate_equiv_value returns the primary collation value for the given
688  * collating symbol specified by str and len.  Zero or negative is returned
689  * if the collating symbol was not found.  This function is used by bracket
690  * code in the TRE regex library.
691  */
692 int
693 __collate_equiv_value(locale_t locale, const wchar_t *str, size_t len)
694 {
695 	int32_t e;
696 
697 	if (len < 1 || len >= COLLATE_STR_LEN)
698 		return (-1);
699 
700 	FIX_LOCALE(locale);
701 	struct xlocale_collate *table =
702 		(struct xlocale_collate*)locale->components[XLC_COLLATE];
703 
704 	if (table->__collate_load_error)
705 		return ((len == 1 && *str <= UCHAR_MAX) ? *str : -1);
706 
707 	if (len == 1) {
708 		e = -1;
709 		if (*str <= UCHAR_MAX)
710 			e = table->char_pri_table[*str].pri[0];
711 		else if (table->info->large_count > 0) {
712 			collate_large_t *match_large;
713 			match_large = largesearch(table, *str);
714 			if (match_large)
715 				e = match_large->pri.pri[0];
716 		}
717 		if (e == 0)
718 			return (1);
719 		return (e > 0 ? e : 0);
720 	}
721 	if (table->info->chain_count > 0) {
722 		wchar_t name[COLLATE_STR_LEN];
723 		collate_chain_t *match_chain;
724 		int clen;
725 
726 		wcsncpy (name, str, len);
727 		name[len] = 0;
728 		match_chain = chainsearch(table, name, &clen);
729 		if (match_chain) {
730 			e = match_chain->pri[0];
731 			if (e == 0)
732 				return (1);
733 			return (e < 0 ? -e : e);
734 		}
735 	}
736 	return (0);
737 }
738